Safety appliance for steam-boilers.



F. L. DORNBROOK.

SAFETY APPLIANCE FOR STEAM BOILERS.

APPLICATlON FILED OCT. 16. 1916.

1,293,730., I Patented Feb.11,1919.

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FREDERICK L. DORNBROOK,

o-E MILWAUKEE, 'WISCONSIN, ASSIGNOR T0 ROBERT ROM, OF MILWAUKEE, WISCONSIN.

SAFETY APPLIANCE Eon STEAM-BOILERS.

Specification of Letters Patent.

Patented Feb. 11, 1919.

Application filed October 16, 1916. Serial No. 125,937.

To all whom it may concern Be it known that I, FREDERIGK L. DoRN- BROOK, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Safety Appliances for Steam-Boilers, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming. a part of this specification.

This invention relates ances for steam boilers.

In practice, steam boilers are commonly provided with tubes projecting therein to the lowest safe water level and equipped with fusible plugs whereby upon an abnormal drop in water level of the boiler with a i to safety appliconsequent drainage of such tube the steam from the boiler passes into the tube and fuses the plug thereof thus finding an outlet to the atmosphere. Accordingly when the water level of the boiler is thereafter raised a new plug must be substituted for the used plug and such substitution has heretofore entailed atemporary shutoff of the tube, removal of the used plug, insertion of a new plug and reopening of the tube. Moreover, this method of substitution has incurred the risk of forgetfulness upon the part of the engineer to reopen the tube after insertion of the new plug.

The present invention relates more particularly to such safety appliances and has among its objects to provide a multiple lug appliance whereby one plug may be su stituted for another by mere valve adjustment.

A further object is to provide an appliance insuring against the exclusion from service of any one plug without substitution of another.

Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawing illustrates one embodiment of the invention and the same will now be described, it being understood that the invention is susceptible of embodiment in other forms falling within the scope of the appended claims.

In the drawing,

Figure 1 shows the appliance in vertical section and as attached to a boiler; and,

Fig. 2 shows a top plan view of said appliance.

' The appliance comprises a casing 1 divided into two chambers respectively provided with fusible plugs 2 and 3 and shutoff valves A and 5. The casing has an intake 6 and is shown as connected to a boiler 7 of ordinary type by a pipe section 8 threaded into its intake and into a plug 9 in the wall of saidboiler, said plug having a pipe section 10 projecting into the boiler, whereby said pipe sections and casing form a tube of the character above mentioned.

More specifically describing the appliance, the casing has a partition 11 separating the plugs 2 and 3 and restricting the chambers formed thereby to communication with the intake 6 through a supply passage 12 in said partition. The partition is provided with openings from said passage into both; chambers and with a tapered valve seat 13 surrounding each of said openings. Also, the partition is provided within and at the base of the chambers with walls inclined toward said opening and preferably slightly curved for a purpose hereinafter set forth. The valves are of like construction and each comprises a washer tapered at both ends and circumferentially grooved intermediate of its ends. The two valves are respectively fixed to alined threaded stems 14. and 15 and are respectively provided with operating handles 16 and 17 and extensions 18 and 19 cooperable to interlock said valves against simultaneous closure. Each stem has a threaded bearing 20 threaded into the casing and provided with the usual bonnet. Also, each earing 20 is provided with a tapered valve seat 21 for the rear end of its respective valve.

Thus assuming use of the appliance with the valves set as illustrated the plug 2 would be active while the plug 3 would be excluded from service. That is to say, the boiler pressure would, under normal condition, force water from the boiler upwardly through the tube into the left hand chamber of the casingl, while the flow of water to the right hand chamber would be shut off by the valve 5. Thus should the waiter level of the boiler drop abnormally with a consequent drainage of the tube the rising steam would be confined to contact with the plug 2, Accordingly, after fusing of the plug 2 the plug 3 could be substituted therefor by merely opening the valve 3 and closing the valve 4:. Thereupon the plug 2 could be replaced at the convenience of the engineer for use alternately with plug 3. Moreover, when making such facile and expeditious substitutions the engineer-would e relieved of all responsibilityastosubse- .quent protection of the boiler for the inter locking extensions of the "valves would in-' sure the opening of the closed Valve to closure of the other.

Again referring to the valves,. .i;tavvill be observed that when in open position for use of their, respective plugs, they will bear against the seatsprovidedgtherefor their bearings 20. aAccording-ly, whenthe plugs fuseitwill be impossible fon-any of the moltenmetal falling; therefrom a to eontact with thev threaded valve stems; ;M0reover,'

it will be observed that: any niolten metal fallingmpon the :valves will tend -to enter and follovv the grooves therein: and !tl,1-us :fall to the bottom of:the plug chambers hereupon with the-partitionwvalls formed asdescribed the same' Will" Wash into the;p;iping of water column.

prior alternatively, said shuto'fi' means insuring connection of at least one of said chambers withsaid-in take --a't allz tiines. Ina fusible plug appliance for steamboilers incombination, a plurality of fusible plugs," means providing separate chambers for said plugs and valves for said chambers providing for use of said plugs alternatively. Ilra fus ble,pl,ug appliance for steam boilers in combination, a plurality of fusible plugs, means providing separate ehambers fora-said plugs and valyes for said chambers providingflfor substitution of one of. said plugs-for ancitherv and insuring opening .of the-chamber of the former upon-closure of the chamberof the latter.

5. .Inaa fusibleplug appliance for steam bo-i-lers in combinationaa plurality ofafusible plugs, a me ns, I .pma'i n separate. chambers therefor; and. separatey operable shutoff valves for said chambers whereby :the ;said

plugs maygbe used, alternatively, vsaid -valves having interlocking lneans insuring open p it -q ngfl tl a t o o h same up closure of the --remainder thereof.

6. Lin a fusible plug ,appliance for steam boilers ain cornbina-tioma housinghavingan intake and being divided into separateplug chambers both communicable ovithisaid intake and separately operableivalves ff orsaid a chamberseto sclQ B the same *atO. said intake, said valves being alined in an; opposedrrelalion and having parts cooperating to insure against simultaneous setting thereof ,in closerLPOSition. I

- In itness whereof, I have hereuntoesubscribed myname.

. 4 ERED IQDORNBRQOK.

- .co iu t thitpatent marbe obt ned tor-five cen eehnby addr fiinz t e,f lemmiss n rvpl la n 1 5' Washington, D. G. a 

